EP 0378440 A2 19900718 - An image forming apparatus.
Title (en)
An image forming apparatus.
Title (de)
Bilderzeugungsgerät.
Title (fr)
Appareil de formation d'images.
Publication
Application
Priority
- JP 476089 A 19890113
- JP 11553289 A 19890509
Abstract (en)
An image forming apparatus includes a first developing device and a second developing device. The second developing device acts on an image bearing member already having a first toner image produced by the first developing device to form a second toner image. The second developing device has a developer carrying member to which a vibratory voltage is applied. A duty ratio of the vibratory voltage is controlled.
IPC 1-7
IPC 8 full level
G03G 15/01 (2006.01); G03G 15/09 (2006.01)
CPC (source: EP US)
G03G 15/0121 (2013.01 - EP US); G03G 15/0907 (2013.01 - EP US)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0378440 A2 19900718; EP 0378440 A3 19901003; US 5066979 A 19911119
DOCDB simple family (application)
EP 90300382 A 19900112; US 46344390 A 19900111